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22 Chemistry of the Nonmetals Solutions to Exercises (d) BaC₂(s) + (aq) + (aq) + C₂H₂(g) (e) 2RbO₂(s) + 2Rb+ (aq) + (aq) + O₂(g) + H₂O₂(aq) (f) Mg₃N₂(s) + 3Mg(OH)₂(s) + 2NH₃(g) (g) NaH(s) + NaOH(aq) + H₂(g) 22.82 (a) - SO₃ (b) - Cl₂O₅ (c) (d) - CO₂ (e) - P₂O₅ 22.83 Sulfur has a total of six valence electrons; its possible oxidation states range from -2 to +6. SO₃ has sulfur in its maximum +6 oxidation state; it cannot lose electrons and serve as a reducing agent. has sulfur in the +4 oxidation state. It can lose electrons, be oxidized and serve as a reducing agent. 22.84 S(g)+O₂(g) SO₂(g) (1) SO₃(g) = (2) H₂SO₄(aq) = -130 kJ (3) AH = 5000 lb 453.6 1 mol 98.09 mol = 1.21 kJ One mole of produces 525 kJ of heat, 5000 lb of produces 1.21 10⁷ kJ. 22.85 (a) + 5; NO₃⁻, + 5 (b) The Lewis structure for would be: The formal charge on N is +1 and on each o atom is -1. The four electronegative oxygen atoms withdraw electron density, leaving the nitrogen deficient. Since N can form a maximum of four bonds, it cannot form a π bond with one or more of the atoms to regain electron density, as the P atom in does. Also, the short N-0 distance would lead to a tight tetrahedron of o atoms subject to steric repulsion. 22.86 (a) Although P₄, and P₄O₁₀ all have four P atoms in a tetrahedral arrangement, the bonding between P atoms and by P atoms is not the same in the three molecules. In the 4 P atoms are bound only to each other by P-P single bonds with strained bond angles of approximately 60°. In the two oxides, the 4 P atoms are directly bound to oxygen atoms, not to each other. Bonding by P atoms in and P₄O₁₀ is very similar. Each contains the cage, formed by four 684